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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?9t2BHxIuixm8Xo30V7psL8sLvi8SKkpLtGamCwW9pQ4Dl949gnKXF9SJkFjW?= =?us-ascii?Q?jHhLMC6sT9qn1aTN/iphM7JiFeCXgmI6PpEK5YqvBvu7DF91ucSO/gEhZ1hA?= =?us-ascii?Q?mKGPXlU7g981PIyrTWmhPKFxPpw2Q5gFJp6v7oKF3d5I+GKb087dBQIv3afw?= =?us-ascii?Q?UjLMNwUC6f4d0pVfBYdk7nKhyB6XnKH7I2p+irTaz4wx5rkxelO9RePWvKdt?= =?us-ascii?Q?R+anC+9kUoCTuPS39eslcEhMirERE9dz6LEBpsbzfpNi2bhcdjmfCaWTbcW9?= =?us-ascii?Q?T9QOjUJE+FL1JRxJtGEH8MM5xF48DN9u5WU+2lSr3upa9tWRF9arsn+stGsr?= =?us-ascii?Q?iM5/ZnPOmqTf7OvBqLxQK9CnJRymb857YQY0szeCfek/Fh8GlTYp+l1I6M/N?= =?us-ascii?Q?6puH0KRfItwCqPYzDCC9gEFG0tRGxmsyTKKcvcEkgka+ANbprq0/e7lP0n3l?= =?us-ascii?Q?oUCvYmcM8Bi1FNBBwmk8K+xG4rAqi+WFKZsrtj95rdMG6POgFkSPYFGmFkjs?= =?us-ascii?Q?MmWxVjifDyNDRqlyIGLByamZ7LfvlAYHjFWzIlfAqCkM34BGRnrDfmw9SFW/?= =?us-ascii?Q?zJAAfLfrDrRrGLH5M39D9yGRKBW+yuG13parcIPcpQihS1aSVOCBme3DF6lf?= =?us-ascii?Q?0yDfAD4jZB4kOTUUMl9B8+PwDXLm7X3X9MJnjYxgg8h6u1D2yCc11VmlQy3a?= =?us-ascii?Q?o8h3tJOhy9cPxgA91xbBQl+y80HqlP6E7o6gFOIVpupiMFckdQFD4woqHBsv?= =?us-ascii?Q?Yh4461p21uXVKPLiXnj7cPoP2thFDYmrSiyV4OTKA9U9x+qhU+akNUeB2/c7?= =?us-ascii?Q?9lfE3KCFxwyub9HCeQdn6a5263QX1Suvsw1xjX7xicJD4GMPeF2Iw+rIk/nB?= =?us-ascii?Q?U8GfLat+oKD8exQ2ZqEtCgsiAzhHXPpzRknuTHEcwk/7LCiXAR3FlRW38Nlx?= =?us-ascii?Q?GmjNb8kre0dQBz+jv5mKbpjmstWXOUoa/JwdPbPvW5I+QHtafq8o+Lie7Q7z?= =?us-ascii?Q?GqGdyMvWEoIBRodUrtHRRcPSHKCeobRMjWSYtw8bVgDHYv1D4J/RpXF8AE0K?= =?us-ascii?Q?HFEsstvsUq4xEgHvPorEUVLolB6zEil3t+1xvaHaKRUrwTYXWIS40ShlUDgc?= =?us-ascii?Q?/Cd16h7/uLAYX18C1L9nWjdMk2TGq3dmbrzG0XAQyls6/eOPGWamDA4C0pLY?= =?us-ascii?Q?+GKoTpTTgSDo96Ea4tZPTKqvQUyTaxJ0+MVsElGMdAedxmISac1+ZTFFyI76?= =?us-ascii?Q?uxSqCdT8uCvwlLA6QlmUKt22ujzePuDVsF2YmkrqRv9oruvPk7QI4p6szA+K?= =?us-ascii?Q?FdZvyCb/ba772Xe+5vwRS3gBOmjFXrhqY7tFvbidqFOF3izIvK/QXOTWwo6F?= =?us-ascii?Q?HPD1RCO6POJVy9Gf+urWS6Jyb0bhy+tPiwBghXpkXcZ5DT4LLlfiTjU96do4?= =?us-ascii?Q?9gqE45CGJD6AR/Tld71Ts8RBqTNqj1w9P41WHS1cgXdS8JTv9jKVxnb2k2EC?= =?us-ascii?Q?HQifwi7w0nWsyQqpHC1OlwJV4FyzvlE9gx7l63Ir7SQAnzalLA4AuhMwd3j+?= =?us-ascii?Q?OVNRO1oLWwQ3ytEHvGM1xUGfWpBJGOJhAHaXXrTiSC4n/My68+jw+Ewyndqb?= =?us-ascii?Q?uQdnpysecfkmRFpJ6fSoLCjDKe2MFWN6HWeg4OuMmeECCwk3pEprrkue19f2?= =?us-ascii?Q?gztfnxqzzsql2SbWxYq6c/nzu35bZct8BuXguF0Un6fFZE60?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: dda1fab5-77d3-4c91-3ea4-08de8f327f1f X-MS-Exchange-CrossTenant-AuthSource: PA4PR04MB9366.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 31 Mar 2026 14:33:37.8367 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: BSG3LuzOEa7XKWy5c8QCQvLPdYR2+I6myV93LoIVHnv/Fuq7BvtlNdXmWrErDx8RFENTRjhal6htpecpgE/eeg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PR3PR04MB7354 On Tue, Mar 31, 2026 at 03:23:11PM +0800, ming.qian@oss.nxp.com wrote: > From: Ming Qian > > Add a new read-only control V4L2_CID_MEMORY_USAGE that allows > applications to query the total amount of memory currently used > by a device instance. > > This control reports the memory consumption in bytes, including > internal buffers, intermediate processing data, and other > driver-managed allocations. Applications can use this information > for debugging, resource monitoring, or making informed decisions > about buffer allocation strategies. > > Signed-off-by: Ming Qian > --- Not sure why not export these information by debugfs, or any benefit vs debugfs? Generanlly document should be first patch, then driver change. Frank > drivers/media/v4l2-core/v4l2-ctrls-defs.c | 8 ++++++++ > include/uapi/linux/v4l2-controls.h | 4 +++- > 2 files changed, 11 insertions(+), 1 deletion(-) > > diff --git a/drivers/media/v4l2-core/v4l2-ctrls-defs.c b/drivers/media/v4l2-core/v4l2-ctrls-defs.c > index 551426c4cd01..053db78ff661 100644 > --- a/drivers/media/v4l2-core/v4l2-ctrls-defs.c > +++ b/drivers/media/v4l2-core/v4l2-ctrls-defs.c > @@ -831,6 +831,7 @@ const char *v4l2_ctrl_get_name(u32 id) > case V4L2_CID_ALPHA_COMPONENT: return "Alpha Component"; > case V4L2_CID_COLORFX_CBCR: return "Color Effects, CbCr"; > case V4L2_CID_COLORFX_RGB: return "Color Effects, RGB"; > + case V4L2_CID_MEMORY_USAGE: return "Memory Usage"; > > /* > * Codec controls > @@ -1476,6 +1477,13 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type, > *min = 0; > *max = 0xffff; > break; > + case V4L2_CID_MEMORY_USAGE: > + *type = V4L2_CTRL_TYPE_INTEGER64; > + *flags |= V4L2_CTRL_FLAG_READ_ONLY; > + *min = 0; > + *max = S64_MAX; > + *step = 1; > + break; > case V4L2_CID_FLASH_FAULT: > case V4L2_CID_JPEG_ACTIVE_MARKER: > case V4L2_CID_3A_LOCK: > diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h > index 68dd0c4e47b2..02c6f960d38e 100644 > --- a/include/uapi/linux/v4l2-controls.h > +++ b/include/uapi/linux/v4l2-controls.h > @@ -110,8 +110,10 @@ enum v4l2_colorfx { > #define V4L2_CID_COLORFX_CBCR (V4L2_CID_BASE+42) > #define V4L2_CID_COLORFX_RGB (V4L2_CID_BASE+43) > > +#define V4L2_CID_MEMORY_USAGE (V4L2_CID_BASE+44) > + > /* last CID + 1 */ > -#define V4L2_CID_LASTP1 (V4L2_CID_BASE+44) > +#define V4L2_CID_LASTP1 (V4L2_CID_BASE+45) > > /* USER-class private control IDs */ > > -- > 2.53.0 >